The present disclosure relates to the field of thermal management of electronics within audio sound devices. In particular, the present disclosure relates to an apparatus with conductive heat transfer and forced convective cooling of components in an audio speaker cabinet.
Audio speaker systems are often enhanced by the use of electronic amplifier circuits having transistors installed inside the cabinet of audio speakers. Such speaker systems are called xe2x80x9cactive loud speaker systems.xe2x80x9d Transistors are limited in the amount of power they can reliably transfer by the operating temperature of the silicon die of the transistor. The semiconductor junction may reach safe normal operating temperatures of about 150 degrees centigrade.
Transistors are mounted on a heat-dissipating device, or heat sink, to transfer thermal energy away from the transistors. A heat sink thermally coupled to a transistor at an operating temperature of about 150 degrees centigrade, can rise to temperatures of about 100 degrees to about 125 degrees centigrade. The effect of thermal resistance of the mounting interfaces between the heat sink and the transistor contribute to the temperatures attained.
Cooling fins are employed with the heat sink in order to increase the surface area of the heat sink, thereby improving the cooling capacity of the heat sink. The cooling fins are placed on the exterior of the audio speaker cabinet to remove the thermal energy to the exterior of the audio speaker cabinet. The cooling fins also serve the purpose of creating a safe distance between the hottest surfaces of the heat sink and the skin of people that handle the equipment.
However, cooling fins also create problems that can inhibit transport of the equipment. Since cooling fins are arranged at the exterior of the equipment, they often present a bulky obstacle on the outer surface of the cabinet. The cooling fins are typically sharp and can cut hands and arms. Cooling fins add to the weight of the equipment, thus inhibiting transportation of the equipment. Fin assemblies are also costly and made of materials that are often brittle and susceptible to fracture and cracking, which can create more sharp edges.
Adding to the problems in the art is the growing demand for improved audio speaker equipment, such as the active loudspeaker system. The active loudspeaker systems have become popular in part for the many uses and convenience they offer. The fundamental design of the active loudspeaker places a power amplifier in the speaker cabinet. Locating the power amplifier inside the cabinet imposes functional operational limitations on the built-in power amplifiers.
Power amplifiers mounted within an enclosed space, such as a speaker cabinet, can present a designer with considerable cooling problems. The thermal energy generated in the power amplifier creates an increase in the air temperature inside the cabinet. As a result, mechanical means that will remove the thermal energy from the electronics within the speaker cabinet is needed. This device should avoid the drawbacks of cooling fins, but still offset the additional heat added to the interior of the cabinet.
The disclosed device is directed towards an active audio speaker system having at least one audio speaker and an amplifier electrically coupled thereto. The active audio speaker system comprises a cabinet having an enclosure defining an interior of the cabinet and an exterior of the cabinet. The interior contains the amplifier: A cooling unit is contiguous with the enclosure of the cabinet. The cooling unit includes a conduction module thermally coupled to the amplifier and a forced convection module at the exterior. The forced convection module is configured to transfer thermal energy from the conduction module.